The invention relates to a switching device, in particular a circuit breaker, for electrical installations, with a housing having terminals.
Such switching devices are employed in various applications as circuit breakers, in particular mains circuit breakers.
Electrical switching devices have to satisfy certain mandated safety regulations. The tight arrangement of electrical switching devices, for example in control boxes, makes it necessary to implement certain safety features for such switching devices.
Regulations, such as the US UL 489, define a minimum separation between the current-carrying conductors of adjacent electric switching devices that are accessible from the outside. For example, for switching devices operating at a voltage UN not exceeding 300 V, an air gap of at least 19.1 mm is required between adjacent current-carrying conductors. For an operating voltage of UN>300 V, the required minimum air gap between two adjacent current-carrying conductors is already 25.4 mm.
Such air gaps between the densely arranged switching devices are implemented by increasing the housing widths. The resulting switching devices have housing volumes or housing widths that would otherwise not be required for their intended function. This not only increases the space requirements, but also the costs associated with their manufacture, storage and transport.